A good example, but... would you get any banding with a 14-bit NEF if you wanted to preserve the highlight detail outside the window and underexposed a stop or two lower?

Eventually you would, depending on how much you pull up the shadows in the process, and you would throw more of the scene into deep shadow, which would make any banding that appears more noticeable. The determinant will be which is more important to you, outside detail, or inside detail? You are still having to compress a 13-15EV DR scene down into a viewing medium with only 9 EV range, and we've already established that banding begins to show in the blackest shadows with a 3 EV or so shadow pull - equivalently, a 1.5 stop underexposure and a 1.5-2 stop shadow pull in your scenario.

Of more concern is color shifting. With a D7000, you can expose for the highlights and pull up the shadows strongly; they'll lose color somewhat (lower color depth in the shadows), but they won't shift green (look up Horshack's tests in mid 2013, this forum), and the noise will remain random. One can deal with the banding with Noise Ninja, but the color shifting is less correctable.

The situation you describe is common in architectural interiors photography. The proper solution would be exposure bracketing and blending in post, or fill flash.

An incidental light reading yielded f/2.8 and 1/30s at ISO 250, which is about 5EV below the correct exposure for a cloudy day at noon (the lighting conditions outside).

That is, I would have had to underexpose by another 2-1/3 stops (4 stops total) just to get the scene outside the window overexposed by only 1 full stop.

I would be inclined to even out the exterior and interior lighting with strobes and umbrellas rather than trying to pull shadows by 4 stops in post-processing but that's just me.